﻿using MySql.Data.MySqlClient;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using 设计;

namespace TP_1
{
    /// <summary>
    /// User的数据访问类：增、删、改、查等操作
    /// </summary>
    class UserDao
    {
        //MySQL的连接串描述
        private static string connStr = "server=localhost;user=root;password=;database=test";
        // private static string connStr = "server=localhost;uid=root;pwd=;database=test";
        /// <summary>
        /// 登录检查
        /// </summary>
        /// <param name="username">用户名 </param>
        /// <param name="password">密码</param>
        /// 
        /// <returns>0：无效 1：登录成功</returns>

        public static int LoginCheck(string username, string password)
        {
            //默认为无效的用户名和密码
            int number = 0;
            //1、构建Mysql连接对象
            MySqlConnection conn = new MySqlConnection(connStr);

            try
            {
                //2、打开数据库连接
                conn.Open();
                //比较用户名与密码的SQL语句
                string sql = "SELECT COUNT(id) FROM `tb_users` WHERE `username`='" + username + "'AND `password`='" + password + "'";

                Debug.WriteLine("SQL语句：" + sql);

                //3、创建SQL命令
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                //4、执行SQL命令
                object result = cmd.ExecuteScalar();
                if (result != null)
                {
                    number = Convert.ToInt32(result);
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine("数据库访问异常……");
                Debug.WriteLine("=============");
                Debug.WriteLine(ex.ToString());
                Debug.WriteLine("=============");
            }
            finally
            {
                if (conn != null)
                {
                    //5、关闭数据库连接
                    conn.Close();
                }
            }



            return number;
        }
        /// <summary>
        /// 获取用户列表
        /// </summary>
        /// <returns>用户集合</returns>
        public static List<User> LoadData()
        {
            //构建用户集合
            List<User> userList = new List<User>();
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                conn.Open();

                string sql = "SELECT * FROM tb_users";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                //3、获取数据访问游标
                MySqlDataReader rdr = cmd.ExecuteReader();
                //4、依次访问数据记录并加入数据集合
                while (rdr.Read())
                {
                    User user = new User();
                    user.Id = Convert.ToInt64(rdr["id"]);
                    user.Username = Convert.ToString(rdr["username"]);
                    user.Password = Convert.ToString(rdr["password"]);
                    user.Nickname = Convert.ToString(rdr["nickname"]);
                    user.IsAdmin = Convert.ToInt16(rdr["is_admin"]) == 1 ? true : false;
                    userList.Add(user);

                }

                //5、关闭游标
                rdr.Close();

            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.ToString());

            }
            finally
            {
                if (conn != null)
                    conn.Close();
            }
            return userList;
        }
        /// <summary>
        /// 按条件获取用户列表
        /// </summary>
        /// <param name="condition">条件参数值</param>
        /// <returns>符合条件的用户集合</returns>
        public static List<User> LoadData(string condition)
        {
            //构建用户集合
            List<User> userList = new List<User>();
            MySqlConnection conn = new MySqlConnection(connStr);

            try
            {
                conn.Open();
                //模糊查询
                string sql = "SELECT* FROM tb_users WHERE username LIKE @username OR nickname LIKE @nickname";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                //安全的参数(占位符)
                cmd.Parameters.AddWithValue("@username", "'%" + condition + "%'");
                cmd.Parameters.AddWithValue("@nickname", "'%" + condition + "%'");

                //3、获取数据访问游标
                MySqlDataReader rdr = cmd.ExecuteReader();
                //4、依次访问数据记录并加入数据集合
                while (rdr.Read())
                {
                    User user = new User();
                    user.Id = Convert.ToInt64(rdr["id"]);
                    user.Username = Convert.ToString(rdr["username"]);
                    user.Password = Convert.ToString(rdr["password"]);
                    user.Nickname = Convert.ToString(rdr["nickname"]);
                    user.IsAdmin = Convert.ToInt16(rdr["is_admin"]) == 1 ? true : false;
                    userList.Add(user);

                }

                //5、关闭游标
                rdr.Close();

            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.ToString());

            }
            finally
            {
                if (conn != null)
                    conn.Close();
            }
            return userList;
        }
        /// <summary>
        /// 新增用户
        /// </summary>
        /// <param name="user">用户数据实体</param>
        /// <returns>MyAQL 自增ID</returns>
        public static long Insert(User user)
        {
            long insertId = 0;
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                conn.Open();
                string sql = "INSERT INTO tb_users "
                    + "(username, password, nickname, is_admin) "
                    + "VALUES "
                    + "(@username, @passwod, @nickname, @is_admin) "
                    ;
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                //参数绑定
                cmd.Parameters.AddWithValue("@username", user.Username);
                cmd.Parameters.AddWithValue("@password", user.Password);
                cmd.Parameters.AddWithValue("@nickname", user.Nickname);
                cmd.Parameters.AddWithValue("@is_admin", user.IsAdmin);
                cmd.ExecuteNonQuery();
                insertId = cmd.LastInsertedId;
            }
            catch (Exception ex)
            {
                Debug.WriteLine("数据输入异常：" + ex.ToString());
            }
            finally
            {
                if (conn != null)
                {
                    conn.Close();
                }
            }

            return 0;
        }
        /// <summary>
        /// 更新用户信息
        /// </summary>
        /// <param name="user">用户数据实体</param>
        public static void Update(User user)
        {
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                conn.Open();
                string sql = "UPDATE tb_users SET "
                    + "username = @username, "
                    + "password = @password, "
                    + "nickname = @nickname, "
                    + "is_admin = @is_admin, "
                    + "WHERE id = @id "
                    ;
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                //参数绑定
                cmd.Parameters.AddWithValue("@username", user.Username);
                cmd.Parameters.AddWithValue("@password", user.Password);
                cmd.Parameters.AddWithValue("@nickname", user.Nickname);
                cmd.Parameters.AddWithValue("@is_admin", user.IsAdmin);
                cmd.Parameters.AddWithValue("@id", user.Id);

                cmd.ExecuteNonQuery();

            }
            catch (Exception ex)
            {
                Debug.WriteLine("数据更新异常：" + ex.ToString());
            }
            finally
            {
                if (conn != null)
                {
                    conn.Close();
                }
            }

        }

        public static void Delete(long id)
        {
            MySqlConnection conn = new MySqlConnection(connStr);
            try
            {
                conn.Open();
                string sql = "DELETE FROM tb_users WHERE id = @id";
                MySqlCommand cmd = new MySqlCommand(sql, conn);
                cmd.Parameters.AddWithValue("@id", id);
                cmd.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                Debug.WriteLine("数据删除错误：" + ex.ToString());

            }
            finally
            {
                if (conn != null)
                {
                    conn.Close();
                }
            }
        }

    }
}
